1. Previous logic can't guarantee left-to-right printing order, so
toolhead may crash on the right side. In the new algorithm printing
order is guaranteed.
2. Clearance radius should be the max of 3 directions (left, bottom,
up), not including right, otherwise collision may happen on bottom or
up directions.
3. Add is_extrusion_cali_object property to handle extrusion brim
overlap better.
Change-Id: I44868b9925d983f5cca0c31d35dfa28d895fadbf